bigsmokey

thinking of replacing my auto trans with a 5 or 6 speed and i have been looking around for parts and i have no problem finding 2wd nv4500 trannys but not able to find many 4wd trannys so can a 2wd be converted to a 4wd. Aslo if anyone has done this i would apreciate any input on how it went. A list of parts would be nice i have a good idea of what i need but i am sure there is something i am forgeting thanks in advance for any tips. Also same question for the nv5400 too can it be changed from 2wd to 4wd.